What is CVE-2026-42427?

CVE-2026-42427 is a medium-severity vulnerability in Openclaw, classified under Incomplete List of Disallowed Inputs. CVSS score: 5.3/10. Published 2026-04-28.

How severe is CVE-2026-42427?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Openclaw

CVE-2026-42427

OpenClaw before 2026.4.8 contains a remote code execution vulnerability caused by missing environment variable denylist entries for HGRCPATH, CARGO_BUILD_RUSTC_WRAPPER, RUSTC_WRAPPER, and MAKEFLAGS. Attackers can inject malicious build tool environment variables to influence host exec commands and achieve arbitrary code execution.

Published 2026-04-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (15.5th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Openclaw — versions 0, 2026.4.8

Weakness classification (CWE)

CWE-184 — Incomplete List of Disallowed Inputs

References

github.com/openclaw/openclaw/security/advisories/GHSA-7437-7hg8-frrw (vendor-advisory, Vendor Advisory)
github.com/openclaw/openclaw/commit/d7c3210cd6f5fdfdc1beff4c9541673e814354d5 (Patch, patch)
www.vulncheck.com/advisories/openclaw-remote-code-execution-via-build-tool-envi… (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-42427?: CVE-2026-42427 is a medium-severity vulnerability in Openclaw, classified under Incomplete List of Disallowed Inputs. CVSS score: 5.3/10. Published 2026-04-28.
How severe is CVE-2026-42427?: Medium severity. CVSS v3 base score is 5.3 out of 10.